Syringe and hub locking assembly



7 0 Z n 4. l/I/l //I 17/ l/z INVENTOR ffl/tn a. fldam ATTORNEYS y 13,1958 J. Q. ADAMS SYRINGE AND HUB LOCKING ASSEMBLY Filed June 6, 1955United rates Patent 9 SYRINGE AND HUB LOCKING ASSEMBLY John Q. Adams,Newark, N. 1., assignor to B'ecton, Dickinson and Company, Rutherford,N. J., a corporation of New Jersey Application June 6, 1955, Serial No.513,482

7 Claims. (Cl. 128-218) This invention relates to a structurally andfunctionally improved syringe assembly and especially an assemblyintended for a one-time use.

It is a primary object of the invention to furnish an assembly includinga barrel and needle; the barrel capable of being prefilled withmedicament which will be maintained in a sterile condition free from anyfactors tending to cause deterioration or contamination. Accordingly,the assembly together with its contained liquid will remain in propercondition for indefinite periods of time. When the assembly is to beused, then, by simple manipulation the cannula may be placed incommunication with the barrel interior so that a hypodermic injectionmay be effected.

A further object of the invention is that of providing an assemblyembodying the advantages set forth in the preceding paragraph and inwhich the needle will be mounted by the barrel in such a manner as toform one rigid unit therewith and in which the connections establishedwill be free from the dangers of breakage or leakage without it beingnecessary to employ washers or other packing or cushioning elements.

Still another object is that of designing a syringe assembly in whichthe barrel or its tip may be formed of suitable plastics includingsynthetic rubber and be capable of being produced in large quantities atrelatively nominal figures; the assembly presenting a pleasingappearance and being usable by a physician or technician in accordancewith ordinary procedures.

With these and other objects in mind, reference is had to the attachedsheet of drawings illustrating one practical embodiment of the inventionand in which:

Fig. 1 is a partly sectional side view of a complete assembly ready foruse.

Fig. 2 is a fragmentary sectional view of the base portion of the needleassembly.

Fig. 3 is a similar view of the outer end of the barrel.

Fig. 4 shows in section the needle and its associated parts mounted uponthe barrelthis view being taken along the line 4--4 in the direction ofthe arrows as indicated in Fig. 5.

Fig. 5 is a transverse sectional view taken along the line 5--5 in thedirection of the arrows as indicated in Fig. 4; and

Fig. 6 is a side elevation of the barrel end as shown in Fig. 3.

Referring primarily to Fig. l, the numeral 10 indicates the barrel ofthe syringe which is preferably furnished with a flange 11 adjacent itsinner or open end. Within the bore ofthis barrel a piston is mounted forreciprocation. That piston may take the form of a stopper 12 ofsynthetic or natural rubber and conveniently furnished with a threadedrecess 13 in its rear face. The barrel is formed of a suitable plasticsuch as polyethylene; the finger flange 11 being likewise formed of thismaterial and preferably integral with the barrel.

Forming part of the syringe is a needle assembly. This embraces,according to the present teachings, a cannula 14 having piercing ends 15and 16. A hub 17 which is cup-shaped and formed of rigid material(preferably metal) has its base portion extended as at 18 and disposedin direct contact with the cannula 14. These parts are secured againstmovements in any desired manner such as, for example, by staking. Theside walls of the cup providing the hub are formed with instruckportions 19 furnishing pawls.

That end of the barrel which is opposite flange 11 provides a tipincluding a head portion having a diameter less than the internaldiameter of the hub cup 17. Below this head the side faces of the tipare recessed as indicated at 21. The recess is interrupted by ribs 22integral with the tip portion and extending axially of the barrel. Inthis manner a minimum of material may be embodied in the tip portionwhile, at the same time, the latter will incorporate maximum strength.The base of zones of each of the ribs may include foot portions 22. Theribs are preferably spaced from each other. The distance between theouter edges of a pair of opposed foot portions 22 will be equal to theinternal diameter of hub cup 17 Head 20 presents a conveniently fiatouter face 23. Centrally of this face, a protuberance 24 may be includedin the assembly. Through this protuberance and into the body of the tip,a bore 25 is conveniently provided. The inner end of this boreterminates in a pier-ceable diaphragm portion 26. The outer end of thebarrel body terminates in a surface 27 perpendicular to the axis of thesame. That surface extends from the face of recesses 21 or the outeredges of foot portions 22 through to the side face of the barrel.

A sheath is furnished to house needle 14. That sheath is preferablyagain formed of polyethylene. It will include a body 28 presenting abore which may be tapered towards the outer sheath end. The diameter ofthat bore should be adequate to freely accommodate cannula 14. Itslength should be in excess of the length of that needle. At its innerend the sheath may include a flange portion 29. Also at this end, thebore of the sheath should have a diameter such that it will snuggly bearin contact with the extended portion 18 of the hub'and the base portionadjacent thereto. At its outer end, the sheath may present a couplingportion 30 embracing screw threads. That portion should have a diametersuch that it may enter into and engage with the threads of the recess 13formed in piston stopper 12.

In use, it will be understood that the bore of the barrel will have beenfilled with medicament in a desired volume. Prior to such filling thebarrel will, of course, have been cleaned and sterilized. This is alsotrue of the other parts of the assembly. Piston stopper 12 will closethe outer end of the bore, thus completely enclosing the medicament andsealing it from escape and contamination as a consequence of this pistonand diaphragm portion 26.

Sheath 28 will have its flange portion 29 disposed to rest against theouter surface of the face of the cup providing hub 17. The adjacent boreportion of the sheath will frictionally engage the extended part 18 ofthis hub. In this manner, the outer end of the hypodermic needle will becompletely protected. The inner end of the same will extend into bore 25and rest in immediate proximity to diaphragm portion 26. Under thesecircumstances pawls 19 will rest against the surfaces of head portion20. They will frictionally bear against those surfaces so that theneedle assembly will be maintained in position.

Now when the assembly is to be used all the operator will have to do isto grasp barrel 10 with one hand and sheath 28 with the other. Movingthe parts axially towards each other, thrust will be exerted by flange29 against the outer face of the hub 17. This will cause the pawls 19 tooverride the head with the skirt or side wall portion of the huboverriding the foot portion 22' adjacent the base parts of ribs 22.Proportioning is resorted to so that the free edge of the cup rides intocontact with surface 27 of the barrel as shown in Fig. 4 under continuedthrust. Simultaneously, the inner face of the base portion of the cuprides into engagement with the outer face 23 of the tip.

The barrel being formed of a slightly compressible or yielding material,a sealing engagement between the cup surface and outer face 23 isassured under these circumstances. Most important a stable support isthus established between these surfaces. Pawls 19 will ride intorecesses 21 and come to underlie head 20 at points between the ribs 22.The edge of the cup being in firm engagement with surface 27, a slightcompressing or indenting of that surface by the cup edges will occursuch that the hub is urged outwardly. Therefore, the free ends of thepawls are forced into firm contact with the underface of head 20. Undersuch conditions, the needle assembly in effect becomes a unit rigid withthe barrel so that a physician by manipulating the latter will cause theneedle to move with it and free from any play of the needle assemblywith respect to that barrel.

Simultaneously with the aforedescribed movements of the parts, the innerpiercing end 16 of the needle will have penetrated diaphragm portion 26as shown in Fig. 4. Accordingly, communication is established betweenthe barrel interior and the lumen of the cannula. The syringe is nowrendered ready for use by simply removing sheath 28 to strip it from theprojecting portion 18 of the hub. Thereupon, coupling portion 30 ismated 'with recess 13 so that the sheath serves as an actuating rod orplunger for the piston 12. Tissue penetration is now effected by meansof the outer needle end 15. An aspirating action may be resorted to byretracting stopper 12. Normally, however, this piston will simply beprojected by exerting thrust on the flange portion 29 of the sheath.Under those conditions the medicament will be expelled through the boreof the needle and injected into the tissues underlying the epidermis.

Thus among others the several objects of the invention as specificallyaforenoted are achieved. Obviously numerous changes in construction andrearrangements of the parts may be resorted to without departing fromthe spirit of the invention as defined by the claims.

I claim:

1. A hypodermic syringe assembly including in combination a barrel, atip at the end of said barrel, a hollow needle having piercing ends, acup-shaped hub secured to said needle at a point intermediate its ends,an enlarged head portion defining the end of said tip, the side face ofsaid tip presenting a receiving recess intermediate said head andbarrel, a pawl carried by said hub and extending into .said recess tolock said hub and needle against removal from said tip, said hubencircling said tip and having its edge in engagement with the outersurface of said barrel and one of the needle ends extending through saidtip into communication with the interior of the barrel, at least certainrecited parts of said assembly being formed of compressible materialwhereby that material will be placed under compression as said hub istelescoped over said tip, whereby to cause said hub to be urgedoutwardly and force an edge of said pawl into contact with an endsurface of said receiving recess.

2. In a hypodermic syringe assembly as specified in claim 1, the depthof said recess and the length of said pawl and the height of said hubbeing such that with the edge of the latter bearing directly in intimateengagement with that surface of the barrel which is adjacent the tip,the base surface of said hub bears in contact with an outer surface ofsaid head.

3. In a hypodermic syringe assembly as specified in claim 2, said barrelbeing formed of compressible material, said hub being formed ofsubstantially rigid material whereby its edge compresses the material ofthe barrel in such surface to urge said hub outwardly and force an edgeof said pawl into contact with the recess surface.

4. In a hypodermic syringe assembly as specified in claim 1, said tipbeing formed with a bore to receive an end of the needle and a diaphragmportion integral with said barrel closing said bore and to be pierced bysaid needle end.

5. In a hypodermic syringe assembly as specified in claim 1, a pair ofribs extending axially of said tip and forming a part of the same, saidribs defining said pawlreceiving recess between them.

6. In a hypodermic syringe assembly as specified in claim 1, an annularseries of ribs forming a part of said tip and extending axially of saidbarrel to define between them a number of such recesses and an annularseries of pawls forming a part of said hub to extend inwardly of thesame one into each of said recesses.

7. In a hypodermic syringe assembly as specified in claim 6, footportions at the base of each of said ribs and the distance between theouter ends of a pair of such foot portions being substantially equal tothe internal diameter of said hub.

References Cited in the file of this patent UNITED STATES PATENTS1,687,502 Marcy Oct. 16, 1928 1,712,070 Cressler May 7, 1929 2,687,727Lawshe Aug. 31, 1954 2,695,613 MacGregor Nov. 30, 1954

